Featured image

This one is not easy to get it, because the folder icons options exclude the featured image checks, in ezg_folder_thumbnail() function.

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To display the featured image as folder icon, I had to customize the whole gallery output,

– add custom gallery_filter

add_filter("post_gallery", "klizg_gallery_filter",10,2);

– add custom ezg_subfolders() action

remove_action('eazyest_gallery_after_folder_content','ezg_subfolders', 5);
add_action('eazyest_gallery_before_folder_content','klizg_subfolders', 6);

– add/replace ezg_folder_thumbnail() with custom code inside custom ezg_subfolders();
and add your custom post_thumbnail_attr() function to check for the icon attributes.

// $attr = $this->post_thumbnail_attr( $post_id );
//
$attr = klizg_post_thumbnail_attr( $query->ID, 'medium' );
$image_html = empty( $attr['src'] ) ? '' : sprintf( '<img width="%d" height="%d" src="%s" class="attachment-thumbnail wp-post-image folder-icon" alt="%s" />',
    $attr['width'],
    $attr['height'],
    $attr['src'],
    $attr['alt']
);
echo $image_html;

// the custom post_thumbnail_attr()
function klizg_post_thumbnail_attr( $post_id = 0, $kli_size = 'thumbnail' ) {
    global $post;
    $post_id = 0 != $post_id ? $post_id : $post->ID;

    $thumbnail_id = eazyest_frontend()->post_thumbnail_id( null, $post_id, '_thumbnail_id' );

    $option = eazyest_gallery()->folder_image;
    $src = '';
    $icon = apply_filters( 'eazyest_gallery_folder_icon', eazyest_gallery()->plugin_url . 'frontend/images/folder-icon.png' );
    if ( 'none' != $option ) {
        if ( 'icon' == $option )
            $src = $icon;
        else {
            if ( ! empty( $thumbnail_id ) ) {
                // $wp_src = eazyest_folderbase()->get_attachment_image_src( $thumbnail_id, 'thumbnail' );
                $wp_src = eazyest_folderbase()->get_attachment_image_src( $thumbnail_id, $kli_size );
                $src = $wp_src[0];
            } else {
                $src = $icon;
            }
        }
    }
    $attr = array(
        'width'  => $wp_src && $wp_src[1] ? $wp_src[1] : intval( get_option( "thumbnail_size_w" ) ),
        'height'  => $wp_src && $wp_src[1] ? $wp_src[2] : intval( get_option( "thumbnail_size_h" ) ),
        // 'width'  => intval( get_option( "thumbnail_size_w" ) ),
        // 'height' => intval( get_option( "thumbnail_size_h" ) ),
        'src'    => $src,
        'alt'    => __( 'Folder Icon', 'eazyest-gallery' )
    );

    return apply_filters( 'eazyest_gallery_folder_thumbnail_attr', $attr, $post_id );
}

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